A Researcher Wants to Determine the Efficacy of a Training

Multiple Choice

A researcher wants to determine the efficacy of a training program directed at improving concentration,focus,and memory on college students.She selects a random sample of 16 individuals and have them take an assessment initial test before the training program,then the individuals complete the training program,and at the end they take a final test that's comparable to the initial test.The results are shown in the following table: The analyst uses a Wilcoxon matched-pairs signed rank test with a 0.05 significance level.The observed z score is ______.

A) −3.4278
B) −3.2157
C) −3.0178
D) −2.9857
E) −2.7978